Square CTF 2018
10 challenges with 53 published community solutions between them. Solution links go to CTFtime’s task page, which aggregates every writeup for a challenge - individual blog posts rot, the aggregator does not.
Full task list on CTFtimeMisc5
Everything that fits no other box: esolangs, puzzles, scripting exercises, and the jail escapes that have not yet earned their own category.
C1: dot-n-dash
8 writeupsSame technique in picoCTF: Permissions, Specialer, Codebook
C2: flipping-bits
6 writeups- modular-arithmetic
Same technique in picoCTF: Permissions, Specialer, Codebook
Same technique in picoCTF: Permissions, Specialer, Codebook
C10: fixed point
3 writeupsSame technique in picoCTF: Permissions, Specialer, Codebook
C7: gofuscated
2 writeups- go
Same technique in picoCTF: Permissions, Specialer, Codebook
Cryptography3
Recover a plaintext or a key from something that was supposed to protect it. In practice: identify the scheme, find the parameter the author got wrong, exploit it.
C8: captcha
10 writeups- math
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
C3: shredded
7 writeups- math
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
C4: leaky power
3 writeups- poweranalysis
- crypto
Same technique in picoCTF: StegoRSA, Timestamped Secrets, AES-ABC
Reverse engineering2
Work out what a compiled program does without its source, then work backwards from the check to the input that passes it.
C6: gates of hell
6 writeups- linux
- reverse
Same technique in picoCTF: file-run2, WinAntiDbg0x100, WinAntiDbg0x200
C9: postfuscator
4 writeups- reverse
Same technique in picoCTF: WinAntiDbg0x100, WinAntiDbg0x200, WinAntiDbg0x300